The Department of Energy MHD Coal-Fired Flow Facility is located on Woods Reservoir at the University of Tennessee Space Institute. Part of the role of UTSI as participants in the DOE program is to document environmental aspects of coal-fired MHD. This document reports the findings of UTSI in investigating a fish kill on Woods Reservoir. The results show the fish mortality to be of natural causes, in no way attributable to CFFF operations. Occasionally seasonal fish kills have occurred in Woods Reservoir during the past several years with minimal documentation of causative factors. During the early spring (April 1980) approximately one hundred fish of a single species Minytrema (spotted sucker) died near the embayment of Rollins Creek. An investigation was conducted to determine the cause of death. Inasmuch as only a single species was involved it was assumed that the kill resulted from an infectious or parasitic disease rather than from pollution. This view was substantiated by an examination of the water quality data during the period. Specimens were examined macroscopically and microscopically for external and internal pathogens. Heavy infestation of the myxosporidian spore Myxosoma sp. was found localized in the gills of the fish. Scanning electron photomicrographs revealed amore » heavy infection by the spores and this coupled with the stress of spring spawning was concluded to be a contributing factor in the death of M. melanops.« less